Well reamer



J. H. HowARD ET Ax. 103,53

WELL 'REAMER Filed June 15, 193 l Patented Dec. 28, 19.37

ED STATES PATENT oFFlcE WELL REAMER Application .lune 15,

9 Claims.

This invention relates to a well tool and relates more particularly to areamer for use in the rotary method of wellvdrilling. A general objectof this inventionV is to provide an improved well reamer embodyingpractical effective means rotatably mounting the roller reaming cutters.

Another object of this invention is to provide a well reamer embodying aplurality of roller reaming cutters positioned and mounted to beoperable to enlarge a well bore to a substantial extent' whereby thereamer is well adapted for enlarging the pilot bore or rat-hole of adeep well.

Another object of this invention is to provide a well reamer of thecharacter mentioned in 5 which the roller cutters are dependably mountedfor rotation in a manner so that they cannot become displaced or lostwhen the tool is in operation.

Another object of this invention is to provide a well reamer of thecharacter mentioned embodying simple, dependable means for removably orreplaceably mounting the rotatable roller cutters. Another object ofthis invention is to provide a well reamer of the character mentioned inwhich the roller cutters and their bearings may be handledand easilyarranged in position on the shank as units.

Another object of this invention isto provide a reamer of the charactermentioned in which the D bearings of the rollerV cutters directlytransmit practically all of the operating thrusts and pressures directlyto the body or'shank thus relieving.

' the pins of these forces.

Another object of this invention is lto provide a well reamer of thecharacter mentioned in which the legs or caps for, supporting the outerends of -the cutter mounting pins may be easily and quickly replacedwhen worn.

A further object oi this invention is to provide 0 a well reamer of thecharacter 4mentioned that is .simple and inexpensive to manufacture andto recondition after use.

The various objects and features of our invention will be readilyunderstood from the following 5 detailed description of typicalpreferred forms and applications of the invention, throughout whichdescription'reference is made to the accompanying drawing, in which:

Fig. lis a side elevation of the reamer provided 0. by this invention'showing it mounted above a pilot bit. Fig. 2 is an enlarged fragmentaryvertical detailed sectional View taken substantially as indicated byline 2 2 cn Fig. 1. Figs. 3 and 4 are fragmentary detailed sectionalviews taken as 5 indicated by lines 3 3 and 4-'-4, respectively, on

1936, Serial No. 85,212

Fig. 2 and Fig. 5 is a fragmentary vertical detailed sectional viewshowing a leg or cap welded to the body.

The improved reamer provided by the present invention includes.'generally, a shank or body Ill, a plurality of roller reaming cutters II and means I2 rotatably mounting the cutters II on the body I0.

The body Ill is an elongate structure or member adapted to be connectedin a well drilling string. In practice where the reamer is to beemployed for the purpose of enlarging a Well having a pilot bore theshank I0 may be'connected with the lower end of a drilling string andmaybe provided at its lower end with a pilot bit. Suitable connecting meansare provided at the opposite ends of the body I0. In the particular caseillustrated in the drawing a tapered screw threaded pin I3 is providedon the upper end of the body Ill to facilitate its connection with thedrilling string and a ,socket I 4 is provided in the lower end of thebody. Fig. 1 of the drawing shows a pin I5 of a pilot bit I6 threaded inthe socket I4 of the body I0. The bit I6 is in the nature of a drag typebit and is adapted to operate in a rat-hole or pilotv bore to guide thereamer. The body I0 may be cylindrical in its general configuration. Inthe preferred construction the lowerportion of the body I0 is reduced indiameter to provide the body with a downwardly facing annular shoulderI1. The shoulder I'I is spaced some distance above the lower end of thebody Ill. A central longitudinal fluid passage I8 extends through thebody I0 from one end to the other to conduct the circulation iluid.

The shank or body I 0 is formed and shaped to receive the cutters Il andthe `cutter mounting means I2. Sets or pairs of recesses I9 and 20 areprovided in the exterior of the body I0 for this purpose. In the reamerillustrated there are three cutters II and the body III has threecircumferentially vspaced pairs of recesses I9 and 20. The recesses I9and 20 are provided' in the exterior of the body III above its shoulderI1. The recesses I9 arev the uppermost recesses and have nat upperwalls. inclined downwardly and inwardly relative to the centrallongitudinal axis of the reamer. The innerl walls 2l of the recesses I9are preferablyflat and are inclined downwardly and outwardly beingnormal to the upper walls of the recesses. A recess 20 is providedimmediately below each recess I9. The recesses 20 are somewhat largerthan the lrecesses I9 and extend downwardly to the body shoulder I1. Theupper walls of the recesses I9 are inclined downwardly and inwardly withrespect to the central longitudinal axis of the tool while the innerwalls of the recesses 20 are inclined downwardly and outwardly and dieout or terminate at their lower ends at the shoulder I1. A partiallycylindrical depression 22 is provided in the inner wall of each recess20. The walls of the depressions 22 are ground or machined to receivebearing parts of the means l2 as will be hereinafter described.l

Flat angular shoulders 23 are provided on the body Il) at the lower endsof the depressions 22.

The cutters I/I are in the nature of roller cutters and are alike insize and shape. The cutters Il are frusto-conical having pitched orinclined peripheries andv flat normal ends. Peripheral cutting teeth 24are provided on the cutters II. The teeth 24 may be straight orspiralled as desired. It may be preferred to have the teeth 24 of onecutter II straight, the teeth 24 of the second cutter spiralled in aright hand direction and the teeth 24 of the third cutter spiralled in aleft-hand direction whereby the teeth of the several cutters cannottrack in their engagement with the earth formation. The ends of thecutting teeth 24 arepreferably bevelled oif at the large ends of thecutters II. Each cutter II is provided with a central longitudinalopening 25. A counterbore or socket 26 is provided in the outer end ofeach cutter II,

The means I2 rotatably mount the cutters II in the recesses 20 forrotation about downwardly and inwardly inclined axes. The means I2include legs or caps 21 projecting downwardly and. outwardly from theupper end of each body recess 23. The caps 21 have their upper portionsreceived in the recesses I9. The upper ends of the caps 21 are at andbear upwardly against the upper walls of the recesses I9 and flat innersurfaces of the caps bear against the inner walls 2I of the recesses I9.The opposite sides of the caps 21 are parallel and cooperate with theside walls of the recesses I9 to prevent lateral movement of the caps.The caps 21 may be connected with the body I0 for easy replacement whenworn. In the structure illustrated in Figs. 1 and 2 of the drawing thecaps 21 are secured to the body I0 by screws 28. The screws 28 areinserted through openings 28b in the caps and are threaded in suitableopenings in the body I0. The heads 28B of the screws are countersunk orrecessed in the outer sides of the caps. The heads 28a are preferablysocketed to permit the easy threading and unthreading of the screws. Thescrews 28 dependably and rigidly secure the caps 21 to the body I 0.

If Adesired the caps 21 may be welded to the shank I0, as illustrated inFig. 5 of' the drawing to, in effect, constitute extensions orcontinuations of the body. When the caps 21 are welded to the body I0they may be welded at their outer sides as well as their inner sides asat 29 and 39 in Fig. 5. In addition to the welding at 29 and 30 thescrews 2,8 may also be employed to assist in securing the caps to thebody. The inner sides of the caps 21 are nat and substantially parallelwith the inner walls'of the body depressions 22. -'The outer lowercorners of the caps .21 are preferably bevelled away. Partially circularor cylindrical depressions 3l -are provided in the inner sides of thecaps 21. The lower ends of the depressions 3I are open at the lower endsof the caps 21. The inner or principal walls of the depressions 3I areparallel with the principal walls of the depressions 22. Flat downwardlyfacing surfaces 32 are provided on the lower ends of the caps 21 at thelower ends of the depressions 3|.

The means I2 for rotatably mounting the cutters I I further includebushings or bearings 33 arranged in the recesses 20. The bearings 33 aregenerally cylindrical and extend through the openings 25 of the cuttersII. A radially projecting annular flange 34 is provided on the outer endof each bearing 33. The ilanges 34 cooperate with the depressions 3| inthe caps 21. The outer surfaces of the flanges 34 are adapted to bear onthe bottom or principal walls of the depressions 3| while theperipheriesof the anges cooperate with the curved peripheral walls ofthe depressions. The anges 34 are sufficiently thick to project inwardlyfrom the inner sides of the caps 21. Extensions or. lugs 35 are providedon the lower parts of the flanges 34 and cooperate with the surfaces 32.The cooperation of the lugs 35 with the surfaces 32 holds the bearings33 against rotation and assists in the transmission of thrusts from thebearings to the caps 21. The inner ends of the bearings 33 areadapted tocooperate with the bottom or principal walls of the body depressions 22.A central longitudinal opening 36 is provided in .each bearing 33. Aportion 33a of reduced diameter is provided on the inner end of eachbearing 33.

The cutters II may be rotatably supported on the bearings 33 throughsuitable anti-friction bearings. In the particular case illustratedseries of anti-friction rollers 31 rotatably support the cutters II onthe bushings or bearings The cutters I I are -arranged with their largeends outwardly. The sockets 26 in the large ends of the cutters IIpartially receive the flanges 30. The flanges 34 operate to space theouter ends of the cutters II from the inner sides of the caps 21. Thecutters li are rotatably supported on the bearings 33 so that theirvteeth 24 project downwardly beyond the lower ends of the caps 21 tocontact the shoulder of earth formation at the upper end of the pilotbore or rat-hole.

'Thrust bearings or thrust washers are provided on the bearings 33 atthe inner ends of the cutters II. In accordance with the invention twowashers 3B and 39 are provided at the.

inner end of each cutter. II. The washers 3B surround the bearings 33 tocooperate with the inner ends of the cutters II. The washers 33 arearranged on the reduced portions 33a of the bearings 33 to cooperatewith the depressions 22 in the body I3. The outer sides of the washers39 cooperate with the inner or principal walls of the depressions 22while the peripheries of the washers engage the peripheral walls oi thedepressions. Flat surfaced lugs are provided on the washers 39 andcooperate with the faces 23 to hold Vthe washers against rotation.Antifriction ball bearings 4I may be providedbetween the opposingsurfaces of each pair of washers 33 and 39. The ball bearings 4I maycooperate with suitable races in the washers 38 and 39. It is to beunderstood that the ball bearings 4I are not essential and that theopposing surfaces of the washers 33 and 33 may have direct contact. s

It is an important feature of the invention that the cutters li, thebearings 33 and 31 and the washers 33 and 33 may be arranged in therecesses El) as units. The washers 39 are pressed on the reducedportions 33a of the bearings 33 and the frictional cooperation of thewashers 33 with the said reduced portions is sui'llcient to retain thewashers 38, the cutters H and the roller bearings 31 on the bearings \33so that the cutter assemblies may be handled and mounted as individualunits. It is to be understood that while the washers 39 are pressed onthe bearing portions 33 to retain the various other parts of the cutterassemblies on `the bearings they may be readily removed when desired.

Shafts or pins 43 are provided to retain the bearings 33 and th'e partscarried thereby in the recesses20. The pins 43'are passed inwardlythrough openings 44, in the caps 21 and extend throughV the openings 36of the bearings 33. The inner end portions of the pins 43 are threadedin openings 45 in the body l0. The openings 44 and 45 are inclineddownwardly and inwardly relative to the longitudinal axis of the reamer.The inclination of the openings 44 and 45 is such that the teeth 28 ofthe frusto-conical cutters ll lare substantially horizontal when theycome into engagement with the shoulder of earth formation in the well.Heads 46 are providedV on the outer ends of the pins 43 and are recessedin theouter Vsides of the caps 21. The inner portions of the pins 43 arethreaded in the openings 45and the heads 46 'of the pins bear on thecaps 21 so that the pins serve to tie the lower portions of the legs 21to the body I9. Ports 50 are provided in the lbody lll and extend fromthe viluid passage 118 to the upper, walls of the recesses 2U. The ports5l] operate to discharge circulation uid downwardly againstthe cutterslli to flush them of mud and cuttings.

It is believed that the operation of the reamer provided by thisinvention will be readily apparent from the foregoing detaileddescription. The cutters il are rotatably. mounted to be rapid andeillcient in their engagement with a shoulder of earth formation in awell bore. The cutters il present cutting edges of substantial lengthand, therefore, are operable to enlarge the bore to a substantialextent. The means l2 rotatably mount the cutters ll for free independentrotation about downwardly and inwardly inclined axes. The cutters aremounted or supported so that they cannot become lost or displaced duringvoperation of the reamer. The anges 3i cooperate with' the depressions3i and the washers 39 cooperate with the depressions 22 to transmit alarge part of the thrusts and operating forces directly to the body l0and caps 21. Accordingly, the pins 43 are not subjected to excessivestrain. The cutting parts 2a of the cut- The cutter assemblies mayy bequickly arranged in position in the recesses 2li as units to be securedto the bodyby the pins 43. VThe cutters il, the roller bearings 21 andthe washers 38 and 39 with the ball bearings 4l may be assem- ,bled on`the bearirigs 33. The frictional engage-l ment of the washers 39 on thereduced bearing portions 33u is such that the washers serve. to

retain the other parts of the assemblies on the bearings 33. The cutterassemblies maybe readily shipped and handled asindividual units formounting onthe body Ill. When the parts becomeworn they may be easilyand quickly replaced. Upon the removal of a pin 43 the cutter assemblycarried by that pin is free for removal from the` body. The assembly maybe readily moved out of the lower end of the recess 20. A new orreplacement 'cutter assembly-is then arranged in the -recesses and issecured in place by the pin 43. When thecaps 21 become worn they may beeasily removed for replace ment. If the legs 21 are welded to the bodyI0 as shown in Fig. 5, the welding at29 and 30 must be removed with anacetylene torch or other means before disconnecting thelegs from thebody. AThe reamerprovided by the present invention is effective inoperation and is inexpensive to manufacture and repair.

Having described only typical preferred forms and applications of ourinvention, we do not wish to be limited or restricted to the specificdetails herein set` forth, but wish to reserve Vto ourselves anyvariations or modifications that may appear to those skilled in the artor fall within the scope of the following claims:

Having described our invention, we claim:

1. A well reamer including, a body vhaving a recess, a cap secured tothe body and extending l downwardly across the outerside of the recess,opposing depressions in the wall of the recess and inner side of thecap, a cutter assembly comprising a bearing having a flange `at one end,

a cutter rotatable on the bearing, and a washer a pin carried by thebody and cap and extending through the bearing to support the assembly.

2. A well reamer including,a body having a recess, a cap secured to thebody and extending downwardly across the outer side of the recess,opposing depressions in the wall of the recess and inner side of thecap, a cutter assembly comprising a bearing havingy a flange at one end,a cutter rotatable on the bearing, and a washer forcibly pressed on theother end of the bearing to be rigid therewith whereby the assembly maybe handled as a unit, the flange and washer beingy adapted to cooperatewith the depressions, and a pin extending through the bearing to supportthe assembly threaded in an opening in the body and having a. headengaging the cap to connect the lower portion of the cap in the body.

3. In a well tool the combination of, a bearing, a ange on one end ofthe bearing, a roller cutter on the bearing having one end'engaging theiiange, and an anti-friction thrust bearing at the other end of thecutter including a Washer on the bearing engaging the other end of thecutter,

a thrust washer removably force-fitted on the bearing, and a row ofballs between said washers, the cutter being held against displacementby the iange and the thrust bearing whereby the assembly may be handledas a unit. y

4. A cutter assembly for a Well tool including, a bearing having aportion of reduced diameter at one end, a radial flange on the other endof the bearing,.a rotatable cutter on the bearing between said portionand. the flange, a thrust washer on the bearing adjacent said reducedportion for cooperating with an end of the cutter, and a second'thrustwasher removably pressed on said reduced portion to retain the cutterand the rst mentioned washer on the bearing whereby the assembly may behandled as unit.

5. A welll reamer including, a' body having a recess, a cap extendingacross the outerl side of the recess, there being opposing depressionsin the inner side of the cap and the wall of the recess, a cutterassembly including, a tubular bearing having a ange at one endcooperating with one of the depressions, a roller cutter on the bearing,and a thrust washer pressed on the bearing to retain the cutter thereonwhereby the assembly may be handled as a unit, the washer .cooperatingwith the other depression, and a pin extending through the bearing andretaining the assembly in the recess.

6. A well reamer including, a body having a recess, a cap extendingacross theA outer side of the recess, means removably securing the capto the body, there being opposing depressions in Ithe inner side of thecap and the' wall of the recess, a cutter assembly including, a tubularbearing having a flange at one end cooperating with one of thedepressions, a roller cutter on the bearing, and a thrust washer pressedon the bearing to retain the cutter thereon whereby the assembly may behandled as a unit, the washer cooperating with the other depression anda pin extending through the bearing and retaining the assembly in therecess.

'7. A well recess and a notch adjacent the recess, a cap extendingacross tlie outer side of the recess, there being opposing depressionsinthe inner side of the cap and the wall of the recess,P a cutterassembly including, a tubular bearing having a iiange at one endcooperating with one of the depressions and a portion of reduceddiameter at the other end, a roller cutter on the bearing having one endcooperating with the flange, a free washer on the bearing adjacent saidportion for reamer including, a body having a cooperating with the otherend of the cutter, a washer on said portion of the bearing cooperatingwith the other depression, and a lug on the last mentioned washercooperating with the notch to prevent rotation of the last mentionedwasher.

8. A well reamer including, a. body having a recess, a cap extendingacross the outer side of the recess, there being opposing depressions inthe inner side of the cap and the Wall of the recess, a cutter assemblyincluding, a tubular bearing having a ange at one end cooperating withone of the depressions and a portion of reduced diameter at the otherend, a roller cutter on the bearing Ahaving one end cooperating with theflange, a

free washer on the bearing adjacent said portion for cooperating withthe other end of the cutter, a non-rotatable washer on said portion ofthe bearing cooperating with the other depression, and an anti-frictionbearing between said Washers.

9. A well reamer including, a body having a recess, a c ap integrallyjoined with the body and extending across the outer side of the recess,there being opposing depressions in the inner side of the cap and thewall of the recess, a cutter assembly including, a tubular bearinghaving a flange at one end cooperating with one of the depressions, aroller cutter on the bearing, and a thrust Washer pressed on the bearingto retain the cutter thereon whereby the assembly may be handled as aunit, the Washer cooperating with the other depression and a pinextending through the bearing and retaining the assembly in the recess.

JOHN H. HOWARD. ALFRED C. CATLAND.

